Method of metal coating



Patented Dec. 28, 1926.

UNITED STATES `PATENT OFFICE.

ALBERT JACKSON, OEPLAINFIELD, NEW JERSEY, AssIeNon ToLHENnYiB. NEWHALL, or PLAINFIELD, New JERSEY.

METHOD OF METAL COATING. I

Application filed May 4,

Henry WPleister filed April l0, 1922, Se-

rial No. 551,373.

One object of this invention is to provide an improved method of dipping the articles to be galvanized, where in some instances, the different kinds of material to be galvanized are run wet from a previous treatthe mass of articles must be interiorly vented to allow the gas and steam thereb formed to escape and thereby obviate the anger of throwing the spelter due to the rapid expansion of steam and thereby preventing explosions or blow-ups when the articles are dipped in wet condition.

Another object of the invention is to provide improved methods for facilitating a rapid and free draininge of lthe liquid spelter when the articles are removed from the metal and for throwing o lthe spelter in the centrifuge, without clogging.

Other objects of the invention are to improve generally the simplicity and efficiency of such methods and to provide a method or process of this kind which is economical and reliable in operation and in the use ofmetal and fuel.

Still other objects of the invention will appear as the description vproceeds;. and -while herein details of the invention are described and claimed, the invention is not limited to these, since many and various changes may be made without departing from the scope of the invention as claimed in the broader claims.

The inventive features for the accomplishment of these and other objects are shown herein in connection with an improved method or process which, briefly stated, includes confining the articles in a mass which is interiorly vented from the bottom of the mass toward the upper part thereof; anddipping the mass into the molten metal. This venting and dipping may be conveniently performed in a container or basket which, briefly stated, includes a substantially cylindrical wall provided with perfo- .off the molten metal.

ment, as when this wet material isl so run 1926. Serial N0. 106,674.

rations and a bottom provided with a lower perforated marginal part and a perforated upstanding substantially cone-shaped intramarginal part extending to near the upper part of the container for venting the mass.

The method herein described and. claimed 00 is the method described in my United States application Serial No. 723,839 filed July 2, 1924, for galvanizing baskets.

In practice I may use one basket for dipping the articles and another for throwing 05 The diliculties heretofore experienced are overcome in the operation'of the two baskets.

' One cone-bottom perforated basket is used for immersing and coating 4the material in 70 the kettle and another cone-bottom perforated basket is used in the centrifuge into which the material is dumped before rotating. vPreferably a smaller basket is used in which the material is loaded when it is immersed into the kettle of molten zinc, while a larger perforated basket is set in the centrifugal machine. -The material, after it has been "coated in the kettle, is dumped from the smaller'basket into theI larger bas- S0 ket. The cone in the bottom of the basket is perforated in the same manner as the sides and bottom.

In the accompanying drawing, showing suitable means for carrying out the process B5 herein claimed,

Fig. l is an axial vertical sectional view of the basket; and

Fig. 2 is a similar view of th ,basket shown in connection with parts of the cen- 00 trifugal machine.

While in practice the ratio of the diameter to height `in the larger basket may be somewhat greater than the same ratio in the smaller basket, the invention is in no way' 95 1 limited to these ratios, nor is the invention limited to baskets of different sizes nor to the use of the smaller baskets as the dipping basket. Therefore, in the drawing the basket sho-wn may representboth baskets.

Herein only enough parts of the centrifugal machine are shown to. explain the opera-- tion'of the basket. These parts include a belt-driven pulley 1 rotatable on a fixed vertical shaft 2 and carrying fast thereon a 105 hub 4 on which is fixed a rotatable table member 5 carrying at one end 6 4counterbalancing means (not shown herein) and the other end a rotatable stud 8 on which is fixed a large gearI 9 supported by thrust bearings 10 and meshing with a pinion 12 fast on the fixed shaft 2.

A table 14 fast on said gear 9 carries a frame 10 comprising bands 11 and a number of uprights 12 mounted fast. on said table.

Rotation of the pulley 1 imparts a planetary motion to the basket 15.

The basket or container 15 is made of mild steel suitable for use in dipping and galwall and provided with perforations registering with the lower perforations 18 of said wall. All of said perforations are small enough to retain in the retainer the smallest articles to be galvanized and large enough to permit the easy passage of molten metal therethrough when dipping the articles or slinging excess metal therefrom.

As shown, the perforated part of the container wall 16 extends from the bottom nearly to the top thereof. The marginal part 20 has a width approximately one-sixth the diameter of the container,`while the coneshaped part 21 has a diameter about twothirds the diameter of the container and a height approximately equal to seven-ninths the height of said perforated part; though the invention is not limited to these exact dimensions.

A strengthening band 25 received and riveted on the upper edge part of said wall 16 has secured thereto, a bail handle 26 coiled to form a middle suspending loop 27 and provided with headed inturned ends 28, passed through and retained in said band and wall for pivotal movement.

A pair of diametrically opposite upstanding brackets 30, 31 (Fig. 1 riveted on said band are provided with loc 'ng openings 32 therein.

A lid 34 disposable on the container is provided with a tongue 35 engageable in one of said locking openings. A guide block 36 on the edge yof the lid opposite to said tongue is provided with a lower uide groove slidably receiving a bolt late 38 and engageable in the locking opening 32 of the basket 30 and having a mani ulating pin 39 passing through a slot 40 in t e block. Said container and the associated parts of the machine are made of metal resistant to the centrifugal force exerted by said metal articles, and also resistant to the heat of molten zinc or other metal and the articles being galvanized.

During the process or method of dipping the small articles inmolten metal for galvanizing said articles, the basket serves for confining the articles in a convenient mass and the cone-shaped part 21 serves to/form a vacant space in the mid part the mass extending from the bottom of the mass to above the middle part thereof, for venting the interior of the mass during the dipping .0f thc mass into the molten metal. This results in the following advantages:

l. Safety to the operators in avoiding explosions or blow-ups when the mass is immersed into the molten metal.

2. More rapid and freer draining of the liquid spelter when the basket is taken from the kettle.

3. Cleaner and quicker ejection of the excess spelter in the centrifuge without clogging the bottom of the basket as is done where a fiat bottom basket is used.

These advantages are further explained as follows: A

Safety-When a flat bottom basket is immersed containing a quantity of small articles, especially such articles as are run better wet with the muriatic acid still on them, great case must be exercised in lowering the or steam may collect underneath or within the mass causing an explosion or blow-up, which in many cases not only throws molten zinc all around the room but also throws basket and contents in alldirections. This ycone-shaped perforated bottom acts as a vent while the basket is being immersed, and with this construction a great improvement has vbeen found in the absence of explosions or blow-ups.

Rapid dmz'nage.-When the basket is/ raised from the molten bath after ithas remained there long enough for'the mass to have acquired the same heat as the zinc, it is necessary yto drain out all liquid spelter as quickly as possible so as to get the material quickly into the centrifuge. With the old tom type the zinc will c og alpl the perforar` tions. The new basket shortens the time required for drainage to a minimum and al- `basket into the zinc bath for bubbles of air lows the material to be dumped into the rotating basket with much less delay than heretofore, thereby allowing the material to go into the machine at a higher temperature than heretofore.

Rapid ejection-Where a flat bottom basket is used, the zinc'which is still in a fluid or semi-fluid state will run to the bottom and remain there and harden sov that after two or three operations the basket is rendered useless until it is placed in the tank' of molten metal to melt ofi' the spelter which hasy adhered to the bottom perforations, and sometimes to the side perforations. With the perforated cone bottom basket the zinc may be expelled through a greater area of perforated Wall, which will prevent it clog-- ging at the bottom of the basket. The excess spelter is more quickly expelled as the mass is more spread out in this basket, which prevents deposits of excess spelter from one article upon another and further prevents one article freezing to another.

I claim:

l'. A method comprising confining articles in a mass with a vent therein; anddipping the mass into molten metal.

2. A method comprising confining articles in a mass with a vent from the exterior to the interior of the mass; and dipping the mass into molten metal.

8. A method of dipping small articles in molten metal, said method comprising confining the articles in a mass with a vent in the interior of the mass from the bottom of the mass toward the upper part thereof; and dipping the mass into the molten metal.

4. A method of dipping small articles in molten metal for coating said articles, said method comprising confining the articles in a mass having an upwardly pointed conical vacant space in the mid part thereof extending from the bottom of the mass to above the middle part thereof, for venting f the interior of the mass; and then dipping the vent is therein.

6. A method of removing excess 'molten metal from small articles, said method comprising dipping the mass in molten metal; confining the articles in a mass having a vacant space in the mid art thereof extending from the bottom of t e mass to above the middle part thereof; and then subjecting the mass to planetary motion.

7. A method comprising dipping a mass into molten metal; confining articles in' a mass in such a manner that the lower part is in the form of a relatively narrow annulus; and then draining the mass.

8. A method comprising di ping small articles in molten metal; con ning the articles in a cylindrical mass with an upwardly pointed conical vacant space in the interior of the mass from the bottom of the mass ioward the upper part thereof; and draining the molten metal from the mass; the lowest diameter of said space being nearly as largeas that of the mass to facilitate draining.

9. A method of removing excess molten metal from small articles during coating;

ysaid method'comprisin'g confining the articles in a mass 'having an upwardly pointed conical vacant space l1n the mid part thereof extending from the bottom of the mass to above the middle part thereof; dipping the mass into the molten metal; draining the mass; and then subjecting the mass to centrifugal force.

Signed at Garwood in the county of Union and State of New Jersey this 12th day. of

April, A. D. 1926.

' ALBERT JACKSON. 

